This application claims priority of International application number PCT/DE99/02972, filed Sep. 14, 1999, which in turn claims priority to German patent application number 198 45 768.5, filed Sep. 22, 1998.
The invention relates to a method and apparatus for electrically controlling and regulating the movement of an electrically operated aggregate of a motor vehicle, more particularly a window lifter or sliding roof.
From DE 33 03 590 C2 a method is known for electrically operating and monitoring the opening and closing cycle of an electrically operated window lifter in which a state of collision is detected indirectly as a result of a suddenly dropping adjusting speed of the window lifter. As a correlation value for the actual adjustment force of the aggregate, the electric current, the torque or the periodic length of the drive motor of the aggregate is measured. As soon as the adjustment force exceeds the maximum permissible limit value an associated control and regulating electronics emanates from a collision state and causes the drive movement of the window lifter to be switched off or reversed.
DE 40 20 351 A1 describes a method for electronically monitoring the opening and closing cycle of an electrically operated aggregate where an unjustified reversal of the movement of the setting member caused by the action of acceleration forces on the vehicle body is prevented through an additional sensor element which detects the appearance of acceleration forces and sends corresponding signals to a control and regulating electronics unit.
In order to take into consideration the acceleration forces which act on the vehicle body, more particularly to consider the vertical acceleration forces which occur when driving over a stretch of rough road it is further known to undertake temporal filtering of the detected correlation value for undertaken through rough road sensors which consider the detected correlation value over a certain time span, as a rule about 30 milliseconds. With the presence of a stretch of rough road the detected signal fluctuates about a mean value and does not rise permanently as in the case of a jamming situation. By considering the signal over a certain time span it is therefore possible to conclude whether it is merely a question of a rough road stretch or a proper case of jamming.
The drawback with this method is that as a result of the need to consider the detected signal over a certain time span, a jamming situation reversing the adjusting movement of the setting member of the aggregate only follows with a temporal delay. This makes it difficult to meet the stringent safety requirements for the safety of motor vehicle window lifting devices.
Finally, it is known from WO 97/39509 to take into consideration a tacho signal for electronically monitoring an adjustment drive mounted in a vehicle in an arrangement for preparing at least one limit value of a closing force restriction or anti-jamming protection system, and to adjust the limit value of the adjustment force in dependence on the tacho signal.
The object of the present invention is to provide a method and apparatus for electrically controlling and regulating the movement of an electrically operated aggregate of a motor vehicle. Thus, it possible in any operating state of the motor vehicle, more particularly in the stationary or parking state, to provide the highest possible degree of security for the anti-jamming system to keep the risk of faulty release of the anti-jamming system as low as possible.
By automatically deactivating the rough road filter when the motor vehicle is at a standstill the sensitivity of the anti-jamming protection system is increased and low maximum permissible jamming forces are produced when the vehicle is stationary. The rough road filter of the anti-jamming system normally undertakes a temporal filtering of at least one correlation value for the adjustment force of the aggregate. When the rough road filter is deactivated and the maximum permissible jamming force (which is equal to the limit value of the adjustment force) is exceeded, the adjusting movement is switched off or reversed without any temporal filtering or delay.
The use of a rough road filter for considering a correlation value of the adjusting movement over a certain time span results in jamming, reversing, or switching off the aggregate with a time delay. By switching off the rough road filter when the vehicle is at a standstill this time delay is reduced or eliminated so that the sensitivity of the anti-jamming system is improved.
The invention thus provides for when the vehicle is at a standstill, a situation where children might possibly play unobserved in the vehicle, with maximum sensitivity of the anti jamming protection system. In a preferred embodiment of the invention, the sensitivity of the anti-jamming protection system is maximum when the motor vehicle is at a standstill so that in the event of children playing in a stationary or parked vehicle, the highest level of safety is guaranteed for the anti-jamming protection system.
In a preferred embodiment of the invention, in order to increase the sensitivity of the anti-jamming protection system when the vehicle is stationary, the limit value of the adjustment force is automatically reduced so that the sensitivity of the anti-jamming protection system is increased. The increase in the sensitivity of the anti-jamming system takes place by reducing the limit value of the maximum permissible jamming force which is detected through a correlation value for the adjustment force of the aggregate.
Whether the vehicle is at a standstill can be detected in numerous ways. The stationary or parked state of the motor vehicle can be ascertained through a switched-off ignition, a removed ignition key, the opening of at least one vehicle door, switching off the engine, opening a seat belt of an occupant or by an occupant getting out of the vehicle.
In the case of a motor vehicle with passive-entry/passive-go system, a stationary state of the vehicle is assumed when the identification transmitter is removed from the motor vehicle. In the case of passive-entry/passive-go systems, an identification transmitter is provided with a transponder through which the vehicle automatically recognizes when the vehicle driver is approaching or moving away, and correspondingly, the doors and windows of the motor vehicle become automatically opened or locked. Further applications are thereby possible.
Furthermore, a stationary state of the motor vehicle can be assumed when the engine is running, the brake pedal is activated and/or no gear is engaged. The same applies to the case where the engine is running, the gear is engaged, and a certain engine speed threshold is understepped. The vehicle is, for example, in the waiting position at traffic lights or shortly before starting off. The last two mentioned variations of the invention have the advantage that lowering the sensitivity of the anti-jamming protection according to the invention is also provided when the vehicle is in the standstill phases during a journey.
Furthermore, the vehicle is advantageously assumed to be at a standstill when remote control is activated for closing the aggregate or closing the vehicle doors or if automatic events take place when the ignition is switched off, e.g. controlled by a rain sensor. Thus, it is often standard for both doors of the vehicle to be locked and the windows to be closed through a remote control. Since persons or animals might possibly still be in the vehicle, the maximum sensitivity of the anti-jamming protection is set. The same applies during automatic closing of the windows, possibly initiated by the rain sensor of a cabriolet. With automatic closing of the aggregate or of the vehicle doors through a remote control, or during automatic events with the ignition switched off, the maximum sensitivity of the anti-jamming protection is set since the driver leaving the vehicle might possibly no longer see a jamming case or hear calls for help.
The limit value of the adjustment force correlating with the maximum permissible jamming force can be set in dependence on the adjusting position, i.e. the lifting position of the aggregate, as is known from DE 33 03 590 C2. It is thereby possible to take into account different local friction forces and to set the maximum permissible adjustment force for each lift position as low as possible. An adaptation of the maximum permissible jamming force to the relevant adjusting position or the friction values can take place, i.e. a self-learning system can be used.
The apparatus according to the invention includes an indirectly detecting anti-jamming protection system with a control and regulating electronics unit which sets the limit value of the adjustment force. In the event of the set limit value being exceeded, the unit sends control commands to the drive unit of the aggregate for reversing or switching off a drive movement. According to the present invention, the control and regulating electronics is connected to means for detecting the stationary state of the motor vehicle, and the sensitivity of the anti-jamming protection is increased when the motor vehicle is stationary.
In addition, the anti-jamming protection system has a filter, more particularly a rough road filter, for the temporal filtering of the detected correlation value for the adjustment force of the aggregate. The control and regulating electronics unit is connected to the filter and deactivates the rough road filter in order to increase the sensitivity of the anti-jamming protection system.
In addition, the control and regulating electronics unit can reduce the adjustable limit value of the adjustment force when the motor vehicle is at a standstill so that the sensitivity of the anti-jamming protection system is increased.
The means for detecting a stationary state of the motor vehicle can be provided by a sensor which recognizes the state of the ignition of the motor vehicle and/or the presence of the ignition key in the ignition lock. Alternatively, or in addition, the closed state of at least one vehicle door, the state of the engine, more particularly the engine speed, the signals of the identification transmitter of a passive-entry/passive-go system, an occupant getting out of the vehicle, or the opening of a seat belt is detected. Furthermore, the stationary state of the vehicle can be detected by means which recognizes activation of the brake pedal, engaging a gear, use of remote-control for closing the aggregate and/or the doors of the motor vehicle, and/or activation of an automatic run of the aggregate when the ignition is switched off. These parameters are detected either directly through corresponding sensor elements or indirectly.
In a preferred embodiment the control and regulating electronics unit is connected through a serial data bus to the means for determining a stationary state of the vehicle. Digital e and data transfer are possible by using digital on-board intelligence systems and a modular construction of the system.
A device is provided for detecting a correlation value for the adjustment force of the aggregate which is connected to the control and regulating electronics unit and which detects the periodic length, the electric current, and/or the torque of the drive motor of the drive unit. A device of this kind is, for example, an electric power meter which permanently detects the power consumption of the drive motor, or an impulse transmitter which detects the rev speed or periodic length of the motor shaft of the drive motor.